#include <stdio.h>
#include <string.h>
#include <stdint.h>
#include <stdbool.h>

#include <common.h>
#include <defines.h>
#include <logging.h>
#include <options.h>


static void tile_calc_flip_gb2bpp(uint8_t * flipped_tile, const uint8_t* src_tile, bool flip_x, bool flip_y);
static void tile_generate_flips(const uint8_t * p_src_tile);

uint8_t tile_permutations[4 * TILE_SZ];
#define FLIP_X_YES true
#define FLIP_X_NO  false
#define FLIP_Y_YES true
#define FLIP_Y_NO  false

// These should match the order of tile flip permutations in tile_generate_flips()
const uint8_t tile_flip_flags[] = {
    CGB_ATTR_NO_FLIP,
    CGB_ATTR_HFLIP,
    CGB_ATTR_VFLIP,
    CGB_ATTR_HFLIP | CGB_ATTR_VFLIP};


const uint8_t bits_reverse_LUT[256] = {
    0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
    0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
    0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
    0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
    0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
    0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
    0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
    0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
    0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
    0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
    0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
    0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
    0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
    0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
    0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
    0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
    0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
    0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
    0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
    0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
    0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
    0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
    0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
    0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
    0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
    0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
    0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
    0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
    0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
    0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
    0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
    0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff,
};


static void tile_calc_flip_gb2bpp(uint8_t * flipped_tile, const uint8_t * src_tile, bool flip_x, bool flip_y)
{
    for (int ty = 0; ty < TILE_HEIGHT_PX; ty++) {
        int y = flip_y ? (TILE_HEIGHT_PX - 1 - ty) : ty;
        flipped_tile[2 * ty]     = flip_x ? bits_reverse_LUT[src_tile[2 * y]]     : src_tile[2 * y];
        flipped_tile[2 * ty + 1] = flip_x ? bits_reverse_LUT[src_tile[2 * y + 1]] : src_tile[2 * y + 1];
    }
}


// Generate all the X/Y flipped combinations of a 2bpp Game Boy tile
// Output is used for testing if CGB flipping map attributes allow for tile pattern deduplciation
//
// tile_permutations[] should be 4 x 16 bytes
static void tile_generate_flips(const uint8_t * p_src_tile)
{
    tile_calc_flip_gb2bpp(&tile_permutations[0 * TILE_SZ], p_src_tile, FLIP_X_NO,  FLIP_Y_NO);
    tile_calc_flip_gb2bpp(&tile_permutations[1 * TILE_SZ], p_src_tile, FLIP_X_YES, FLIP_Y_NO);
    tile_calc_flip_gb2bpp(&tile_permutations[2 * TILE_SZ], p_src_tile, FLIP_X_NO,  FLIP_Y_YES);
    tile_calc_flip_gb2bpp(&tile_permutations[3 * TILE_SZ], p_src_tile, FLIP_X_YES, FLIP_Y_YES);
}


// bool tileset_find_matching_tile(unsigned int source_tile_id, unsigned int * TileCountDeduped, uint8_t * new_tile_id, uint8_t * new_attribs)
bool tileset_find_matching_tile(const uint8_t * src_tile, const uint8_t * tile_set_deduped, const unsigned int tile_count_deduped, uint8_t * new_tile_id, uint8_t * new_attribs)
{
    tile_generate_flips(src_tile);

    for (unsigned int index_dedupe = 0; index_dedupe < tile_count_deduped; index_dedupe++) {

        for (size_t f = 0; f < ARRAY_LEN(tile_flip_flags); f++) {
            if (memcmp(&tile_set_deduped[index_dedupe * TILE_SZ], &tile_permutations[f * TILE_SZ], TILE_SZ) == 0) {

                // Match Found
                *new_tile_id = (uint8_t)(index_dedupe & 0xFFu);
                *new_attribs = (index_dedupe < CGB_TILES_START_BANK_1) ? CGB_ATTR_TILES_BANK_0 : CGB_ATTR_TILES_BANK_1;
                *new_attribs |= tile_flip_flags[f];
                // log_debug(" * Tile Dedupe MATCH. new ID -> %d (dedupe count=%d), new_tile_id=%d, new_attribs=0x%02x, flip_index=%d\n", *new_tile_id, tile_count_deduped, *new_tile_id, *new_attribs, f);
                return true;
            }
        }
    }
    return false;  // No match found
}

